Mammoth Cave in Kentucky is the world's longest known cave system. The Jewel Cave system near Custer, South Dakota is ranked as the second longest known cave system.
60 inches found just south of rutland North Dakota in august 2010
The world's longest river system is the Nile-Kagera River system that flows in eastern Africa. There is some suggestion that the Amazon-Ucayali-Apurimac system in South America may be the largest.
chile
its in wall,south dakota
Andes is the Longest mountain chain in south america.
Probably North and South Dakota and Alaska.
The Andes
Nebraska and South Dakota
The Amazon River in South America is the longest river in the world. Tennessee does not border it.
south dakota
Longest - yes, largest - no, the Amazon River in South America is.
South America, the Andes